I suggest you ...

Limit outgoing mail messages

Please add new feature to limit the number of outgoing emails Yes this is a very bad that we cannot limit outgoing emails!

One of our hosting customers was a spammer. Because of their spamming our IP was blacklisted.

We removed the blacklist and suspended the spammer, but during that time our other customers were very upset, their emails weren't being received...and new customers of ours couldn't receive download letters sent from us, it was a terrible problem! Then they would complain but support tickets weren't received, either!

Parallels, please add a feature (like cPanel) where we can limit the number of emails any user can send in a day/hour/etc so we wont have this same problem again.

Controlled at all levels down to single mailbox. Covering shell/CGI/cron scripts, mod_php/Apache scripts and, of course, SMTP traffic. We will identify which mailbox (smtp), or domain (mod_php/apache), or system user (cron/shell) has sent this pile of emails which blacklisted the server. Actually even better – the one cannot send over limit, so the server will not be blacklisted at all.

P.S.
If you are not interested in preview and only interested in production release day, you would need to watch Parallels announcements at (http://www.parallels.com/about/subscribe/). The ones who decided to attend Parallels Summit 2014 (http://www.parallels.com/summit/2014/) will probably know the dates sooner than others and also will have a chance for more insight and talk to us directly with your questions and suggestions.

We have spotted several comments here urging us to ship the function sooner. Since only 9 out several hundred people chosen to watch comments of others, we decided it is the best to respond in status field.

We know spam problem might be very acute for you, and we understand you urge. So let us explain – “Started” status in the forum actually means the function is in development. And saying “in development” I would literally mean programmers typing on their keyboards for a purpose of shipping this function in next Plesk 12.0 release. There are no releases in between now and Plesk 12.0, so the function physically cannot be delivered sooner than it is already planned unless developers start hitting keyboard faster, so please have a little patience. We want this problem solved fully and with high quality.

We will soon enable the function in Plesk 12.0 preview which is already available for download http://forum.parallels.com/showthread.php?294313-Plesk-12-0-Preview
So if you are interested in the function, I would recommend you to get Plesk 12.0 installed and start review. Once update is available, your installation will get it. We are very much interested in your evaluation.

If you are not interested in preview and only interested in production release day, you would need to watch Parallels announcements at (http://www.parallels.com/about/subscribe/). The ones who decided to attend Parallels Summit 2014 (http://www.parallels.com/summit/2014/) will probably know the dates sooner than others and also will have a chance for more insight and talk to us directly with your questions and suggestions.

So please have a little patience, get Plesk 12.0 preview installed and once the function enabled (very soon) – the status will be updated.

Thank you very much and hope you will like the function once it is available

Plesk is not, and I guess will never be the solution for every single problem you might encounter as a webmaster. It automates everyday tasks and make our job much easier by providing the click-and-go approach for many administrative tasks, but eventually everything still depends on our knowledge. Can't blame Plesk alone for what happened.

I have implemented cluebringer (cbpolicyd) some time ago, limited authenticated email accounts to 100 messages per hour / 1000 per day, and I have a special group for throttled accounts: 10/50. The cron script monitors the log and if some user hits the limit and persists on trying to send mail more than XX times, he automatically gets the mail notification and gets throttled. If he still persists, Fail2Ban blocks his IP address for the next 1 day.

I think I won't even bother turning on the new Plesk's feature when it becomes available.. :)

Finally decided. I am switching to cPanel. Gave Plesk a chance for many years. Yesterday my server allowed a compromised email account send thousands of spam mail. We are listed in three different spam lists now. This is the second time on this year this happens.
Thank you Plesk.
In a few months??? suuure, bah, we needed it for yesterday!

I had an email account compromised yesterday and over 1 million email ended up in the queue. Once the queue gets over a thousand email in it the web interface for the Mail Queue will not load. You are forced to use command line at that point. We need a way to limit email very soon or we will be forced to look at another Control Panel solution. Not everyone that is using Plesk has command line access.